Locomotive



2 Sheets-Sheet 1- E .M g A fig A. W. BRUCE LOCOMOTIVE Filed Jan. 24. 1924 March 17, 1925.

wrrzrfsszs Z March 17, 1925. 1,529,984

' A. W. BRUCE LOCOMOTIVE Filed Jan. 24. 1924 2 Sheets-Sheet 2 Patented Mar. 17, 1925.

UNITED STATES ALFRED w. nation, or nnwvonign. Y.

Loooiyiorivn'.

Application fi1edJanuary'24, 1924. Serial No. 688,176.

To aZZ whom it may concern:

its; and, (b), to attain a more even torque of the pistons of "the forward cylinders and reduce the liability to slipping'of the group of driving wheels acuated by them;

'llheimprovcment claimed is hereinafter fully set forth. 1 i

In the accompanying drawings: Figure 1 isa diagrannnatic side view, in elevation,

of a Mallet locomotive engine in which my invention is applied; Fig. 2, a plan or top view of the same, with the boiler removed; and, Figsfi and a, diagrammatic vertical transverse sections, on the lines a a and Z) 6, respectively, of Fig. 1.

My invention is herein exemplified as applied in a Mallet locomotive, the boiler, 1, of which is, asin prior and present practice, supported on a rear group of eight driving wheels, 2, journalled in bearings in a main frame, 2, connected to the boiler without the capacity of relative lateral movement, and on a forward group of driving wheels, 3, journalled in a supplemental frame, 3, which is pivotally connected to the main frame, so as to have the capacity of swivelling movement about the axial line of its ipivotal connection, relatively thereto. The rear and front groups of driving wheels are, as heretofore, independently connectedto, and rotated by, the pistons of separate sets of steam cylinders.

In the practice of my invention, referring descriptively to the specific embodiment thereof which is herein exemplified, steam, from the boiler, 1, is supplied, through valve governed steam supply pipes, 5, 5, to the valve chests of a pair of steam cylinders, 4, 4 supported on the main frame, 2, the pistons of which cylinders are coupled, in the usual manner, to one of the pairs of driving wheels of the rear group, 2, and steam is exhausted from said Be it known that I, ALFRED W. BRUCE,

cylinders, into the smoke box,'1 of the boiler, through exhaust pipes, 49, 4 and 4 The pipes, 4 and 46, extend forwardly,

onopposite sides of the boiler, ata greater distance apart than the locomotive frames, and are connected, attheir forward ends, to the pipe, 4, which leads to anexhaust pipe and nozzle in the smoke box.

The wheels of the supplemental frame, 8 of the locomotive, are actuated bythe pistons of a set of cylinders supportedflon said frame, and consisting of a middle cylinder, 6,. and two side cylinders, 6, 6 The pistons of the cylinders, 6, 6* and 6 of the supplemental frame, are coupled to crank pins on one of the. axles of the drivingxwheels, 8, of the forward group, and live steam from the boileris supplied to said-cylinders through pipes, 5 and 5, which extend forwardly, in line with the steam supplypipes,5, 5", of the cylinders of the rear group of driving wheels, and

are articulated thereto by joints, 5, of the ordinary construction. The-steam pipes, 5 and 5', lead into a transverse front channel section, 7, which is incontinuously open communication with the valve chests, 8, 8, and 8 of the cylinders,'6, G and 6 respectively As shown in Fig. 3, the channel section, 7, is cast integral with thecylinders, 6, 6 and 6,

but such specific structural form is not es sential, as the channel section may, without departure from my invention, be made as a separate pipe, connecting the steam supply pipe with the valve chests of said cylinders. Steam is exhausted from the cylinders, 6, 6 and 6, through a pipe, 9

joint, 9 is fitted in the apart than, the locomotive frames, 'and that, except for their short front sections, the exhaust pipe lines are similarly disposed. By such location, free space is afforded for the installation of the connections of the piston of the middle cylinder,

6, with the crank pin of the axle which it actuates.

It will be seen that the following substantial advantages are attained by the application of my invention in a Mallet lo- 7 leadlng to an exhaust pipe and nozzle, in

comotive. The more uniform torque and increase of tractive power within deter-- mined width limits, which have beenproven, to d be resultant upon the application of three cylinders, in locomotives of" other types, have not heretofore been available'in Mallet locomotives, by reason of structural conditions, as the space between theside;

members of the forward supplemental frame, is so materially obstructed as: to; prevent the installation of'the valveroperating mechanism of three cylinders, as well as to interfere with the crank axle and mam connecting rod of. the mlddle cyhnev der. My invention, hereinbeforedescribed,

being fully exempt'from this -objection,the-

application of three cylinders, in connection with either or both groups-10f wheels of lVIallet locomotives, is rendered fully practicable.

lVhile, in the embodiment of; my invention which is herein set forth, thedriving wheels of the rear group areshown as-be ing rotated by the pistons of two cylin-. ders only, my invention is not" limited to such specific construction, as: three: cylin-U ders may be applied. in connection with the driving wheels of said rear group, without departure from the spirit and-operative principle of my invention.

I claim as my invention, and desire to secure by Letters Patent:

1. In a locomotive of the Mallet type, the combination of a rear group of driving wheels; a front group of driving wheels; cylinders, the pistons of which actuate the rear group of driving Wheels; means'for effecting exhaust directly to the atmosphere from said cylinders, three cylinders, the pistons of which actuate the frontrgroup of driving wheels; and means; for efiecting exhaust to the atmosphere from said cylinders.

2,,In4 a locomotive of the Mallet type, thecombination of a rear group of driving wheels; a front group of driving wheels; cylinders, the pistons of which actuate the rear group of driving wheels; three cylinders, the :;pi stons.of which actuate the front group of driving wheels; steam supply pipe lines, connecting'thevalve chests of all the cylindersdirectly withthe boiler, and. ex tending:-longitudinally on, opposite sides of the frame.ofrthecylinders of the-rear group;

exhaust; steam pipe, lines, connecting the valve chests,- ofr-the. rear cylinders with the smokehox, and comprising two side sections leading forwardly from the valve chests of: the, rear cylinders and a short central section locatedbetween said side section andthe-forwardcylinders; and independent exhaust steam lines, leading from the cylinders of; the front and the rear groups, respectively, ,to :the atmosphere,

ALFRED V. BRUCE. Witnesses;

J. Snowmen BELL, Eran-5A. WADSWQRT L 

